While looking for ways to activate the developer menus left over in Animal Crossing, including the NES emulator game selection menu, I found an interesting feature that exists in the original game that was always active, but never used by Nintendo. In addition to the NES/Famicom games that can be obtained in-game, it was possible to load new NES games from the memory card. I was also able to find a way to exploit this ROM loader to patch custom code and data into the game, allowing for code execution via the memory card.

Last summer I began reverse engineering Animal Crossing for the GameCube to explore the possibility of creating mods for the game. I also wanted to document the process to create tutorials for people interested in ROM hacking and reverse engineering. In this post I explore the developer debugging features that are still left in the game, and how I discovered a cheat combo that can be used to unlock them.